1. Field of the Invention
The present invention is directed to a process for the extraction of contaminants from plastics, e.g. plastic bottles and plastic beverage dispensing lines. More specifically, the present invention is directed to extracting contaminants from plastics by the application of an alcohol to a plastic surface.
2. Description of the Prior Art
One problem encountered in the use of post-mix beverage dispensing systems is that impurities remain in the plastic lines when a line is converted from dispensing a pungent flavored liquid such as root beer to a delicate flavored beverage such as Sprite.RTM. (a registered trademark of The Coca-Cola Company). Specifically, root beer contains methyl salicylate which is absorbed by and adsorbed on the plastic tubing. When a root beer line is converted to dispense Sprite.RTM., the residual methyl salicylate causes the Sprite.RTM. to develop an objectionable taste. Preliminary evaluation results indicate that root beer contamination in Sprite.RTM. at a level of 15 ppm methyl salicylate is detectable though not objectionable. Beyond a methyl salicylate concentration of 20 ppm, the Sprite.RTM. is not acceptable. If the methyl salicylate concentration is 10 ppm or below, the Sprite.RTM. product is acceptable and has virtually no detectable root beer flavor.
Another major problem encountered in the beverage industry is the present inability to recycle and refill containers such as PET plastic two liter bottles. There is a strong need to remove chemical contaminants, dirt and soil, and microbiological contaminants so that the beverage contained in the plastic bottle will have below the allowable daily intake levels (ADI) of contaminants and thus the plastic bottle could be recycled. Once this recycling is achieved, production costs will be reduced considerably.